Finding the Fourth Proportional to 13,388.89, 18,476.63 and 7,420.50

Step by Step Solution

1. Step 1: Write the proportion equation
   13,388.89 : 18,476.63 = 7,420.50 : x
2. Step 2: Convert to fraction form
   13,388.89/18,476.63 = 7,420.50/x
3. Step 3: Cross multiply
   13,388.89x = 18,476.63 × 7,420.50
4. Step 4: Simplify right side
   13,388.89x = 137,105,703.43
5. Step 5: Solve for x
   x = 137,105,703.43/13,388.89
6. Step 6: Final answer
   x = 10,240.26